package org.broadinstitute.sting.utils;

import java.util.List;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.regex.Pattern;
import java.util.regex.Matcher;

/**
 * Common utilities for dealing with text formatting.
 *
 * @author mhanna
 * @version 0.1
 */
public class TextFormattingUtils {
    /**
     * The default line width, for GATK output written to the screen.
     */
    public static final int DEFAULT_LINE_WIDTH = 100;

    /**
     * Simple implementation of word-wrap for a line of text.  Idea and
     * regexp shamelessly stolen from http://joust.kano.net/weblog/archives/000060.html.
     * Regexp can probably be simplified for our application.
     * @param text Text to wrap.
     * @param width Maximum line width.
     * @return A list of word-wrapped lines.
     */
    public static List<String> wordWrap( String text, int width ) {
        Pattern wrapper = Pattern.compile( String.format(".{0,%d}(?:\\S(?: |$)|$)", width-1) );
        Matcher matcher = wrapper.matcher( text );

        List<String> wrapped = new ArrayList<String>();
        while( matcher.find() ) {
            // Regular expression is supersensitive to whitespace.
            // Assert that content is present before adding the line.
            String line = matcher.group().trim();
            if( line.length() > 0 )
                wrapped.add( matcher.group() );
        }
        return wrapped;
    }

    /**
     * Compares two strings independently of case sensitivity.
     */
    public static class CaseInsensitiveComparator implements Comparator<String> {
        /**
         * Compares the order of lhs to rhs, not taking case into account.
         * @param lhs First object to compare.
         * @param rhs Second object to compare.
         * @return 0 if objects are identical; -1 if lhs is before rhs, 1 if rhs is before lhs.  Nulls are treated as after everything else.
         */
        public int compare(String lhs, String rhs) {
            if(lhs == null && rhs == null) return 0;
            if(lhs == null) return 1;
            if(rhs == null) return -1;
            return lhs.toLowerCase().compareTo(rhs.toLowerCase());
        }

    }

}